According to all your comments, I see the following:

dxdt was a global variable, with a reference in the report
- correct it was just dxdt

Is your cursor defined in more than one place?
just one place

Do all definitions now include that new field?
so yes (defined in one place)

Is the correct FRX FRT being used?
should be because it is compiled into the APP

That is, can yu be sure the report that is running is the one that should be running? it should be

Thanks for the help. The report only runs once a week. So I am sure I will hear about it on Friday if it messes up again.